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so,ok like seth had 'laid" with his sister?Im just trying to figure out where our generation started.and I got as far as seth married his wife..? where did she come from?I stopped cause ,now im confused??
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user3868Jan 30 '13 at 18:49

"Daughters" is plural, so Adam and Eve apparently had at least two girls. The wording of Gen 5:4 could be taken to mean that they had "sons" (again plural) after Seth, and Seth was born after Cain and Abel, so that could mean three named sons plus at least two more. Note Cain, Abel, and Seth are mentioned by name because of their roles in the first murder. The other children's names are not given because they are not part of any specific events included in Genesis. The vast majority of the people who lived in "Genesis time" are not named, just as most people living at any given time are ...
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JayJun 22 '12 at 7:55

... not mentioned by name in the history books.
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JayJun 22 '12 at 7:55

And to those who believe in the literal interpretation of Genesis, adam lived more than 900 years! If we only live about 80-90 years and some have 4 or 5 children, imagine Adam and Eve! Also God gave them a command to fill the Earth so i'm pretty sure it would have been more than 5 children.
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jlaverdeJul 25 '14 at 13:47

Sin is said to come from one man (Ro 5:12). Adam (and Eve) are pointed to as the "source" of sin/death. The curse that God pronounced upon them in Ge 3 after they disobeyed God affects us because we are their descendants and will inevitably sin (Ro 3:23).

God didn't immediately make Eve in the same manner as he made complimentary genders for the other animals. Ge 2 tells of how God showed Adam that he was alone before creating Eve. If God created other humans who were not descendants of Adam and Eve, did he do the same for them? Would he need to?

Would these others have been in the Garden of Eden, too? When did they sin (presuming they did), and when were they expelled from the garden?

@Jomet, Typical readings of the text suggest that once created, every plant/animal reproduced in the manner in which God designed "after [its] kind." There's no other mention of God (re-)creating any of the creatures (or creating more than one pair). While the text does not exclude the possibility, the mere fact that they are never mentioned (or referred to by other Biblical authors, who occasionally refer to elements of tradition for which there is no mention in the OT) is a reasonably strong suggestion that there weren't any others.

Attempting to make room for other humans who weren't descendants of Adam and Eve is not completely impossible, given what's written, but it certainly requires crafting some complicated stories to fit the facts if there were any.
It really sounds like the Biblical account leaves very little room for other people being created simultaneously.

Cain's wife was almost certainly a descendant of Adam and Eve (most likely their daughter).

14 Behold, you have driven me today away from the ground, and from
your face I shall be hidden. I shall be a fugitive and a wanderer on
the earth, and whoever finds me will kill me.”

This appears to suggest that there were "others" besides Adam and Eve. While someone could take the story of Adam and Eve literally as the first humans, it doesn't imply that they were the only humans - just the only humans that we talk about.

Therefore Cain's wife MAY have been one of the "others". Else there would have been an incestuous relationship:

Cain was the first born son of Adam and Eve, and Abel was the second.
In Genesis 4 we read how Cain kills his brother and is sent east of
Eden where he marries a woman and “lays” with her. Because Adam and
Eve were the first humans – assuming ONLY humans – Cain’s wife
was his sister – and, consequently, all of the early Biblical
relationships were incestuous (with the exception of Adam and Eve).